Agriculture is always a juggling act, requiring producers to constantly monitor commodity markets, input pricing, and so many other variables. In crop farming, those variables usually mean an understanding of markets and inputs like seed, fertilizer, and fuel. But it also requires the producer to monitor more volatile or production-sensitive aspects of the operation, like how the weather is impacting moisture retention, soil erosion, or germination, or how the cost/benefit analysis of certain management techniques can impact overall profitability.
For many US crop farmers, the process of managing surface residues on variable soil types is one example of cost/benefit analysis for profitability. In most areas of the US, glaciation and prehistoric climactic pressures formed various taxonomic types of soils, which means it’s not uncommon to have multiple soil suborders, subgroups, or soil series in a single field. As a recent report by the USDA’s Economic Research Service explained,
“USDA’s Natural Resources Conservation Service (NRCS) has identified soil health as a key focus for soil management. Conservation tillage, which protects the soil by reducing soil disturbance and keeping the soil covered, is considered to be a key component of a soil health management system.”
Utilizing conservation tillage as a method for managing soil productivity – and therefore profitability in crop farming – is tied closely to crop selections/rotations, residue types, and weed control challenges. Tillage practices that help to size, redistribute, and integrate surface residues into the soil profile with minimal soil disturbance help soils retain moisture and minimize erosive influences.
But tillage also breaks up surface matting, allowing for warmth to penetrate the soil and work with retained moisture in a way that fosters seed germination – a process that many contend is harder to promote in cooler, no-till-managed soils, which can, in turn, lead to lower yields. While studies have shown soil temperatures under no-till management eventually even out when compared to conventional (moldboard/offset) tillage, some tillage prior to planting gives plants a boost during germination and advanced growth stages.
A study from the Illinois Department of Agriculture alluded to the connection between tillage, soil management, and yield when it measured yields and residues produced by varying types of tillage over a three-year average (see chart below) as part of a statewide comparison project to better understand the relationship between tillage, soils, and yields.
The highest yields came from fields utilizing a mulching tillage style while the lowest came from no-till systems. As expected, no-till systems showed a greater residue cover, but also showed lower bu/A yields. Balancing the need of the soil for organic matter and a seed’s need for warmth and moisture control shows some disruption – with care paid to sizing and maintaining organic residues – as a yield-bearing middle road.
This study didn’t measure the use of tillage as a weed management tool. However, the authors advised that “an extra cost for additional or more expensive pesticides may be associated with some conservation tillage systems. For example, a burndown herbicide may be needed with no-till and ridge tillage systems.” Since fuel and pesticide/herbicide prices are typically tied (since both require fossil fuels like crude oil and natural gas to produce), tillage that disturbs weed seeding and germination may cost dollars immediately in fuel but may pay for itself in offsetting the cost of additional pest and weed control inputs.
The intersection between profitability and tillage isn’t linear and it’s definitely not standalone. Much depends on other variables: input costs, soil types, crop rotations, even the types of residues left from previous years’ crops. But in weighing the variables and assessing decisions based upon cost-benefit analysis, producers can turn tillage into a tool for building their crop production profitability.
Source: K-Line Ag